Phonographic apparatus



Oct. 29, 1940. E. w. KELLOGG PHONDGRAPH IC APPARATUS Filed July 29, 1939 ous motion between the surfaces which are fricor catching, and, moreover, lubricationis im- Patented Oct. 29, 1940 UNlTED STATES PATENT OFFICE Edward W. Kellogg, Moorestown, ltl. J., assignor to Radio Corporation of America, a corporation of Delaware Application July 29, 1939, Serial No.- 287,293

4 Claims. (01. 274-13) This invention relates to phonographic apaforesaid in which more uniform cutter feed is paratus of the type employing a cutter head obtained. which is moved radially across a blank disc to Still anotherobject of my present inventionis cut a groove therein, and more particularly to to provide an improved disc recording'mac im the driving and guiding mechanisms for the cutin which the reaction of the load of the cu er h carriage on the turntable driving system willbe In recording machines of this type, the cutter greatly reduced. i is usually mounted on a carriage arranged for It. is also an' object of my present invention sliding movement on a pair of guide rails. Such to p in a machine of the pe S for an carriages are made quite heavy, and the friction improved carriage mounting which is simple in 10 between them and the guide rails is usually sufco struct on a d highly eflloient in operation. ficiently great to make the lead screw by means According to t e present invention, I provide of which the carriage and cutter are driven guide rails in the form of round bars (that-is, across the turntable require enough power t r bars which are circular in cross-section) and act appreciably on the turntable driving system, cause'these to rotate in journal bearings, the 15 thereby impairing the speed constancy of the rails supporting the cutter head carriage for slidrotating turntable and record blank. To reduce ing movement thereqll- Thus, e elat ve m0- the aforementioned friction, it is possible, of 171011 be ee .the guide rails and the cutter carcourse, to employ ball bearing rollers. However, riage is p c pa y'at right angles to the direcspace does not always permit use of such rollers, tion of travel of the carriage in sliding along the 20 and even this expedient does not completely rails. The rotation of the rails can be slow, and eliminate irregularities in friction, owing to parsince a variation i their p e s e ect on ticles of dirt or slight rough spots on the rails, the travel of the cutter ca the rails can as well as bearing imperfections. Such irregube driven independe y 9 h le. nilarities affect the uniformity of' motion of the ploying a source of power which will not be 5 cutter carriage, and the least imperfections in harmed by any irregularities in this small load. this respect become apparent on the surface of The novel features that I consider characteristh record; tic of my invention are set forth with particular- In accordance with my invention for the purity in the-appended claims. The invention itself, pose of minimizing friction on the rails, I m k however, both as to its organization and method 30 use of the principle that when there is continu-' of operation, together with additional objects and advantages thereof, will best be understood from the following description of one embodiment thereof, when read in connection with the accompanying drawing, in which tionally engaged, a change in direction or velocity of the relative motion has comparatively little effect on the frictional force developed between the two surfaces." In other words, the increment-a1 friction is almost zero. It is particulargly advantageous if the continuous motion is at right angles to the motion for which the minimi zing of friction is desired. There is, with this superimposed motion, no possibility of sticking 35 Figure 1 is a top plan view of a disc recording machine employing one form of my invention, and

Figure 2 is a side elevation thereof.

Referring more particularly to the drawing, 4 wherein similar reference numerals designate corresponding parts throughout, "there is shown 0; frame oomprising bed plate I ;-provlded-" with a pair ofspaced standards 3. 'The plate l'supports a motor 5 which, through a belt 1,-drives a 4| pulley 9 on a turntable shaft II, the shaft H carrying a record supportin'g turntable l3 at its upper end.

Fixed to the shaft II is a. worm IS in mesh with a gear I! which, through gearing l9, drives 50 a lead screw 2| adapted todrive a sound translating device, such as a cutter 23, across a blank proved. ya better o'f 'oil. or grease.

The primary object'of my present invention is to provide an improved disc recording machine which will be free from the aforementioned objections.

More particularly, it is an object of. my invention to provide, in machines of the type set forth, a mechanism for feeding and guiding the cutter across the record with the friction load on the 1ead screw greatly reduced. record disc R on the turntable l3. The cutter Another object of my present invention is to is carried on a head 25 which is fixed to a carprovide improved phonographic apparatus as riage 21' slidably carried ona pair of parallel 55 ings 21a in the carriage 21.

guide rails 28 and 29 rotatably carried in the standards 3 and extendingthrough journal bear- The weight of the carriage 21 is transmitted to the rails 28 and 29 through bearings 21a. The rails, in turn, are supported in stationary bearings 30 in the standards 3. The guide rails 28 and 29 are disposed adjacent the turntable and are circular in crosssection,-as are also the bearings 21a. Motion is imparted to the carriage 21 and the parts carried thereby through a half nut or the like 26 in engagement with the lead screw 2| in conventional manner, any suitable mechanism 42, of which many are well known in the art, being employed to disengage the half nut 26 from the lead screw 2| when desired.

One of the standards 3 supports a motor 3|, the shaft of which is provided with a worm 33 in mesh with a gear 35 on a shaft 31. On.the opposite end of the shaft 31 is a gear 39 which meshes with the gear 4| of a train of gears ll, 43, 45, the gear ll being fixed to the guide rail 28 and the gear being fixed to the guide rail 29. The gears of this train are connected to the lead screw 2|.

When the motor 5 is energized, power is delivered therefrom to the carriage 21 through the belt I, the pulley 9, the shaft ||,-its worm IS, the gears l1 and I9, and finally the lead screw 2| and the half nut 26 to effect movement of the carriage mechanism longitudinally of the guide rails 28 and 29 and thus movement of the cutter 23 radially across the record blank R. At the same time, the motor 3| may be energized to effect rotation of the guide rails 28 and 29 in the journal bearings 21a, the rotation of the guide rails 28 and 29 taking place in a direction at right angles to the movement of the carriage 21. This greatly reduces the friction load on the lead screw 2|, thereby reducing the reaction of such load of the turntable driving system, and thereby insuring more uniform feeding of the cutter 23 across the record blank R.

Although I have shown and described but one embodiment of my invention, it will be apparent to those skilled in the art that many other-variations thereof are possible. I, therefore, do not wish to limit myself except insofar as is made necessary by the prior art and by the spirit of the appended claims.

I claim as my invention:

1. In phonographic apparatus, the combination of a turntable, guide means rotatably disposed adjacent said turntable, a sound translating device slidably carried by said guide means for longitudinal movement thereon relative to said. turntable, means including a motor for sliding said device along said guide means, and a second motor coupled to said guide means for rotating said guide means during sliding movement of said device thereon.

2. In phonographic apparatus, the combination of a frame, a pair of guide rails rotatably carried on said frame, means including a motor for rotating said guide rails, a carriage slidably mounted on said guide rails for longitudinal movement thereon, a sound translating device on said carriage, and means including a second motor for sliding said carriage along said rails while said rails are rotating.

3. The invention set forth in claim 2 characterized in that said guide tails are circular in cross-section, and characterized further in that said carriage is provided with a plurality of journal bearings through which said guide rails extend.

4. In a phonographic apparatus, the combination of a frame, a turntable rotatably supported on said frame, a pair of guide rails of circular cross section rotatably carried on said frame, said guide rails being parallel to each other and to said turntable, a motor carried by said frame and coupled to said guide rails for rotating said rails,

a carriage having a plurality of journal bearings thereon, said guide rails extending through said bearings and said carriage being slidable longitudinally on said guide rails, a sound translating device on said carriage, a second motor carried by said frame, carriage feeding means for positively feeding said sound translating device across a record'on said turntable, ineans for selectively coupling said carriage to and uncoupling said carriage from said feeding means at will, and

power transmitting means interposed between said second named motor and said carriage feeding means for driving said carriage feeding means separately from said guide rails. 

